The
Imagery of Leaven

Many of the images in the Bible are obvious
to us. We understand God as a shepherd, or being under the protection
of his wings. But one image that is not readily apparent is that of leaven,
at least to us in the modern world. I used to scratch my head at the regulation
that for one week each year all leavening had to be removed from dwellings
of the Israelites. What is negative about the little packets of yeast
that I use when I make bread? It seems like an odd requirement that for
Passover and for the week after, during the Feast of Unleavened Bread,
it was so necessary to live without yeast. As we are approaching the time
of Passover and Easter/Resurrection Day, it is good to think about what
God was saying through that image.

We can learn something about it from food preservation and bread-making
in ancient times. Whenever grain or flour is allowed to get moist, within
a few days it will acquire a sour taste and later get moldy - the normal
process of decay. It comes from yeasts and molds in the air that start
growing and producing acids. The microbes will also produce carbon dioxide
and sometimes alcohol in this process of fermentation. Without steps taken
to prevent it, this will always occur over time.

Far
back in ancient history someone discovered that at an early point in the
process, when the dough is still edible, it can be baked and the acid
and bubbles will add texture and flavor to the bread. It normally takes
a few days before fermenting and rising occur naturally, but it can be
greatly hastened by inoculating the lump of dough with a little of an
old lump that has been aging longer. So the tradition started to take
out a lump of dough made each day and keep it until the next day, and
add to the next batch. (Sourdough breads today are still made this way
by adding a "starter" dough from an earlier batch.) The lump
of old dough would become sour and inedible overnight, and if left longer
it would become rancid and rotten. But yet it would be mixed into the
new lump of dough to cause it to rise.

Once we see this picture of ancient bread-making, it becomes much more
obvious why leavened dough (hametz in Hebrew) became an image of a life
contaminated by sin. The decay that would lead to "death" or
rottenness was added to each batch. Without it the dough tends to be sweet,
but adding it would give the dough a slightly sour taste that would get
stronger and stronger until it was baked. (Ancient breads probably tasted
more like sourdough bread.) Think of how sin tends to "sour"
our personalities, and also cause us to "puff up" with pride.
Eventually, as Adam first found out, sin leads to our decay and death.

It is interesting to see the motif of original sin here - that the infection
had to have started with the first lump of dough that was leavened a long
time ago, like Adam committing the first sin. Each lump of dough after
that would get its decay from the dough made the day before, like sin
being transmitted from generation to generation.

Most of the time this is a negative image, and Jesus uses it that way
when he says "Beware of the leaven of the Pharisees and Sadducees" (Matt 16:6). But once he transforms the image to use it in a positive
way, to describe the kingdom of heaven. He says that the kingdom of heaven
is like leaven because you can put a very small amount of leavened dough
into a very large mass, and it will have a potent effect on the whole
thing. He is describing the powerful effect of the gospel and how even
a few faithful believers can quickly transform the world around them.
Here he isn't really referring to the image of decay but as the ability
of a very small amount of dough to cause a transformation of the whole
dough. May we be like leaven in this way!

But
the most powerful image of leaven is in the Passover meal that Jesus celebrates
with his disciples as the Last Supper. When Jesus holds up the bread and
says "This is my body" he certainly would have been holding
up unleavened bread, or matzah, because the Jews were required to eat
the Passover meal with unleavened bread (Deut 16:1-3). He wasn't just
speaking about his body as bread in general, but as this specific kind
of bread, made without leaven, unadulterated by decay. Unlike the rest
of humanity who had been leavened with sin inherited from their fathers,
he had not been infected with the "rottenness" that was in the
rest of mankind.

By using this image he is saying another thing about himself: that he
was fit as a sacrifice because he was free of leaven. All animal sacrifices
offered up to God had to be without blemish, and any grain offerings offered
up to the Lord by fire had to be free of leaven (Lev. 2:11, 6:17). It
seems that when God prohibited his people 1500 years earlier from eating
leaven during Passover, he was thinking ahead to when Jesus would use
the bread at the Passover meal to describe himself. Because he is not
leavened with sin, he is a suitable sacrifice, and because he is not infected
with decay, he is God's Holy One who will not see decay and will live
on eternally! (Psalm 16:10, Psalm 49:9, Acts 13:34-37).

Paul
and the other early Jewish believers understood this picture of leaven.
Paul uses this image along with the fact that Passover came on the first
day of the seven-day Feast of Unleavened Bread to describe how Jesus'
sacrifice should enable us to live righteously:

"Do you not know that a little leaven
leavens the whole lump of dough? Clean out the old leaven so that you
may be a new lump, just as you are in fact unleavened. For Christ our
Passover also has been sacrificed. Therefore let us celebrate the feast,
not with old leaven, nor with the leaven of malice and wickedness, but
with the unleavened bread of sincerity and truth." 1Cor 5: 6 -
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